1. Field of the Invention
The present invention relates to an input unit for recognizing position movement according to a change of an input signal in a mobile terminal. More particularly, the present invention relates to a method and an apparatus for continuous key operation that uses an input unit for recognizing position movement of an object relative to the input unit according to a change of an input signal.
2. Description of the Related Art
An optical mouse denotes a mouse that projects light onto an object and is used to move a cursor displayed on a screen by detecting movement of an object relative to the mouse using light reflected off the object. That is, the optical mouse sends a coordinate determined according to a change of position of the object to a terminal. A terminal controls the movement of the cursor displayed on the screen based on the coordinate provided from the optical mouse.
A recently developed optical mouse, referred to as an ‘optical joystick’, may be used to move a cursor on a screen of a mobile terminal by detecting a finger's movement. That is, the mobile terminal controls the movement of a cursor on the screen by detecting a change of an image (fingerprint shape or characteristic of a finger surface) using light from a Light Emitting Diode (LED), which is a light source that may be used in the optical joystick. In addition, the mobile terminal may be provided with a directional key operation using the optical joystick as illustrated in FIG. 1.
FIGS. 1A and 1B illustrate directional key operations using an optical mouse according to the conventional art.
More particularly, FIG. 1A illustrates a directional key operation using an optical joystick according to the conventional art, and FIG. 1B illustrates a continuous directional key operation using an optical joystick according to the conventional art.
As illustrated in FIG. 1A, when a coordinate change in a downward direction is detected by the optical joystick, a mobile terminal provides an operation of a down directional key (↓).
At this point, since the optical joystick detects a coordinate change with respect to only a change of an object, the operation of FIG. 1A should be repeatedly performed as illustrated in FIG. 1B in order to continuously provide the operation of the down directional key (↓).
As described above, the optical joystick provides a cursor movement or a directional key operation using a change of a position of an object that is detected using light reflected off the object. Therefore, in the case where a user views a long address book or long contents of an email in a mobile terminal, which uses the optical joystick, the user of the mobile terminal is inconvenienced by having to repeat the same operation, as illustrated in FIG. 1B.